PreparationFor salsa verde: Combine all herbs in medium bowl. Whisk in vinegar and mustard, then gradually whisk in oil. Season salsa verde to taste with salt and pepper. Cover and let stand at room temperature until ready to use, up to 2 hours. For seafood stew: Bring fish bones, skin, and head and 5 cups water to simmer in large saucepan over medium-high heat. Reduce heat to medium and simmer until broth is reduced to 4 cups, about 30 minutes; strain broth into bowl. Heat oil in heavy large pot over medium-low heat. Add onion, fennel, and garlic. Sauté until very soft but not brown, about 25 minutes. Mix in crushed red pepper; stir 1 minute. Add tomato paste and stir until beginning to darken, about 5 minutes. Add broth and olives and bring to simmer. Add all fish and seafood. Simmer uncovered until clams open and fish and squid are just opaque in center and tender, 6 to 8 minutes (discard any clams that do not open). Season seafood stew to taste with salt and pepper. Toast bread. Cut each slice in half. Place 2 bread halves in each of 4 shallow bowls. Ladle stew over bread, dividing equally. Drizzle stew with salsa verde. Serve, passing remaining bread and salsa verde separately. Ingredient tip:Cerignolas are large green Italian olives. They are brinecured and have a delicate, sweet taste. Castelvetranos are medium-size brinecured green olives grown primarily in Sicily near their namesake town. They are mildly sweet and salty. Both types of olives are available at some supermarkets and at specialty foods stores.
PreparationFor salsa verde: Combine all herbs in medium bowl. Whisk in vinegar and mustard, then gradually whisk in oil. Season salsa verde to taste with salt and pepper. Cover and let stand at room temperature until ready to use, up to 2 hours. For seafood stew: Bring fish bones, skin, and head and 5 cups water to simmer in large saucepan over medium-high heat. Reduce heat to medium and simmer until broth is reduced to 4 cups, about 30 minutes; strain broth into bowl. Heat oil in heavy large pot over medium-low heat. Add onion, fennel, and garlic. Sauté until very soft but not brown, about 25 minutes. Mix in crushed red pepper; stir 1 minute. Add tomato paste and stir until beginning to darken, about 5 minutes. Add broth and olives and bring to simmer. Add all fish and seafood. Simmer uncovered until clams open and fish and squid are just opaque in center and tender, 6 to 8 minutes (discard any clams that do not open). Season seafood stew to taste with salt and pepper. Toast bread. Cut each slice in half. Place 2 bread halves in each of 4 shallow bowls. Ladle stew over bread, dividing equally. Drizzle stew with salsa verde. Serve, passing remaining bread and salsa verde separately. Ingredient tip:Cerignolas are large green Italian olives. They are brinecured and have a delicate, sweet taste. Castelvetranos are medium-size brinecured green olives grown primarily in Sicily near their namesake town. They are mildly sweet and salty. Both types of olives are available at some supermarkets and at specialty foods stores.